Respiration in Plants – NEET 2025 Complete Notes (With Diagrams & PYQs)

-



🌿 Introduction – Energy ka Real Source!

Hello NEET Aspirants 👋
Aap sabko pata hai — photosynthesis me plants energy banate hain 🌞
Lekin kya aapko pata hai plants apni energy use kaise karte hain?
Wahi process hota hai Respiration — plants ke liye life ka “powerhouse” system ⚡

Respiration = Controlled oxidation of food to release energy (ATP form).

Yani, photosynthesis me food banta hai 🌿 aur respiration me wahi food energy me convert hota hai 🔋

🌱 1. What Is Respiration in Plants?

Definition (NCERT):

“Respiration is the process of breakdown of glucose to release energy for cellular activities.”

Simple words me:
Glucose → Energy (ATP) + CO₂ + H₂O

💡 Trick:
Photosynthesis = Storage of energy
Respiration = Release of energy

🌾 2. Types of Respiration

TypeOxygen UseEnd ProductsATP ProducedExample
AerobicPresentCO₂ + H₂O38 ATPMitochondria
AnaerobicAbsentEthanol + CO₂2 ATPYeast
FermentationAbsentLactic acid2 ATPMuscles

💡 Trick:
“Aerobic = Efficient, Anaerobic = Emergency backup!” ⚡

🔋 3. Overall Reaction of Aerobic Respiration

C6H12O6+6O2→6CO2+6H2O+686kcalC_6H_{12}O_6 + 6O_2 → 6CO_2 + 6H_2O + 686 kcal

Energy is released as ATP molecules — the energy currency of cells 💰

🌿 4. Stages of Cellular Respiration

Respiration me energy release ek stepwise process me hota hai —

🔹 1. Glycolysis (Cytoplasm)

🔹 2. Link Reaction (Mitochondrial matrix)

🔹 3. Krebs Cycle (Mitochondrial matrix)

🔹 4. Electron Transport Chain (ETC) (Inner mitochondrial membrane)

🧪 5. Glycolysis – The First Step of Respiration

📍 Location: Cytoplasm
📍 Discovered by: Embden, Meyerhof & Parnas

Meaning:
“Glycolysis” = Glucose breakdown (Glyco = sugar, Lysis = breakdown)

🧬 Process:

  1. Glucose (6C) → splits into 2 Pyruvate (3C each)

  2. Net ATP Gain:

    • ATP used = 2

    • ATP produced = 4

    • Net gain = 2 ATP + 2 NADH

💡 Trick:
“Glycolysis = Cytoplasmic power plant.”

🔁 6. Link Reaction – Connecting Glycolysis & Krebs

📍 Location: Mitochondrial matrix
📍 Reaction:
Each Pyruvate (3C) → Acetyl CoA (2C) + CO₂ + NADH

💡 Enzyme: Pyruvate dehydrogenase
💡 ATP: No direct ATP produced

🔥 7. Krebs Cycle (Citric Acid Cycle / TCA Cycle)

📍 Location: Mitochondrial matrix
📍 Discoverer: Hans Krebs (1937)

Main Function:
Complete oxidation of Acetyl CoA to CO₂ and release of energy (NADH, FADH₂, ATP)

🔹 Steps Simplified:

  1. Acetyl CoA (2C) + Oxaloacetic acid (4C) → Citric acid (6C)

  2. Citric acid gradually oxidized → CO₂ released

  3. NADH, FADH₂, ATP generated

⚡ Products (per glucose molecule):

ProductPer Glucose
CO₂4
NADH6
FADH₂2
ATP2

💡 Trick:
“Krebs = King of Energy Cycle 👑”

⚙️ 8. Electron Transport Chain (ETC)

📍 Location: Inner mitochondrial membrane
📍 Main Job: Convert NADH & FADH₂ → ATP (via oxidative phosphorylation)

🧬 Key Points:

  • Series of electron carriers (Complex I–IV)

  • Oxygen acts as final electron acceptor

  • Water is formed as by-product

  • Total ATP = 34 ATP (approx.)

💡 Trick:
“ETC = Electricity Transport Channel ⚡”

🔋 9. Energy Yield in Cellular Respiration

StageATP
Glycolysis2
Krebs Cycle2
ETC34
Total38 ATP (in prokaryotes), 36 ATP (in eukaryotes)

🧬 10. Anaerobic Respiration (Fermentation)

Occurs without oxygen, usually in yeast, bacteria, or muscle cells.

OrganismEnd ProductExample
YeastEthanol + CO₂Alcohol fermentation
Muscle cellsLactic acidAfter heavy exercise

💡 Trick:
“No O₂ = No problem, make alcohol or lactic acid!” 🍺

⚖️ 11. Respiratory Quotient (RQ)

RQ=CO2 evolvedO2 consumedRQ = \frac{CO_2 \text{ evolved}}{O_2 \text{ consumed}}
SubstanceRQ ValueExample
Carbohydrates1Glucose
Fats< 1Tripalmitin
Proteins~0.9Amino acids
Organic acids> 1Malic acid
Anaerobic∞Yeast

💡 Trick:
“RQ = CO₂ out / O₂ in”

🌾 12. Amphibolic Pathway – Dual Role of Respiration

Respiration serves both:

  • Catabolic function: Breakdown of molecules

  • Anabolic function: Precursors for biosynthesis

Hence, it’s called an Amphibolic pathway.

🧠 13. NEET PYQs (2017–2024)

YearQuestionAnswer
2024Site of glycolysisCytoplasm
2023End product of fermentation in yeastEthanol
2022Total ATP in aerobic respiration38 ATP
2021Final electron acceptor in ETCOxygen
2020RQ for carbohydrate1
2019Enzyme in link reactionPyruvate dehydrogenase

🧾 14. Quick Revision Table

StageLocationEnd ProductsATP
GlycolysisCytoplasm2 Pyruvate + 2 NADH2
Link ReactionMitochondriaAcetyl CoA + NADH0
Krebs CycleMitochondriaCO₂ + NADH + FADH₂2
ETCInner membraneH₂O + ATP34

🎯 15. NEET Strategy Tips

✅ Remember all 4 stages with location
✅ Practice RQ values & reactions
✅ Revise enzyme names (Pyruvate Dehydrogenase, NADH Dehydrogenase)
✅ Learn total ATP gain chart
✅ Go through NCERT diagrams line-by-line

“Respiration is not just breathing, it’s the energy of life!” 🌿

🔗 Related Blogs


Comments

Post a Comment

Popular posts from this blog

Celebrating Teacher’s Day 2025: Honoring the Architects of Knowledge

-
Image
The Origin of Teacher’s Day Teacher’s Day in India commemorates Dr. Sarvepalli Radhakrishnan, born on September 5, 1888. A philosopher, statesman, and the second President of India (1962–1967), Dr. Radhakrishnan believed education was the cornerstone of progress. When students and admirers suggested celebrating his birthday, he humbly proposed that the day be dedicated to honoring all teachers instead. Since 1962, September 5th has been celebrated as Teacher’s Day across the country, a tradition that continues to thrive. Why Teachers Matter Teachers are more than just educators—they are mentors, role models, and catalysts for change. On this Teacher’s Day, let’s reflect on their impact: Shaping Minds: They introduce students to new ideas, critical thinking, and problem-solving skills. Building Character: Beyond academics, teachers instill values like discipline, empathy, and resilience. Inspiring Futures: Many successful individuals credit a teacher for sparking...
Read more

🌱 Plant Kingdom – Bryophytes (Mosses & Liverworts) | NEET 2025 Notes

-
Image
Introduction Bryophytes are often called the “Amphibians of the Plant Kingdom” because they require water for reproduction but can survive on land as well. They form a crucial link between algae and pteridophytes. For NEET aspirants, bryophytes are an important NCERT-based topic that often appear in exams with direct questions. --- General Characteristics of Bryophytes Non-vascular plants (no xylem or phloem) Plant body is thalloid (undifferentiated into true root, stem, and leaves) Anchored by rhizoids instead of roots Reproduction occurs through spores Life cycle shows alternation of generations (gametophyte dominant, sporophyte dependent) --- Classification of Bryophytes Bryophytes are divided into three main groups: 1. Liverworts Example: Marchantia Plant body is dorsiventral, thalloid Asexual reproduction: by fragmentation and gemmae Sexual reproduction: male and female sex organs borne on separate structures 2. Mosses Example: Funaria, Polytrichum Gametophyte has two ...
Read more

NEET 2025 – Cell: The Unit of Life | NCERT-Based Notes + Diagrams

-
Image
Post Content: Introduction: "Cell: The Unit of Life" is a conceptual and factual chapter. NEET 2025 can include diagram-based MCQs and questions from cell organelles and types of cells. Focus on NCERT keywords and functions. 1. Discovery of Cell Discovered by Robert Hooke in 1665 (cork cell) Cell Theory by Schleiden & Schwann Rudolf Virchow: "Omnis cellula-e-cellula" – cells arise from pre-existing cells 2. Prokaryotic vs Eukaryotic Cells Feature Prokaryote (Bacteria) Eukaryote (Plants/Animals) Nucleus Absent Present Organelles No membrane-bound Membrane-bound Ribosome Type 70S 80S Cell Wall Peptidoglycan Cellulose (plants) 3. Cell Organelles Nucleus: Double membrane, contains nucleolus and chromatin Mitochondria: Powerhouse, double membrane, has its own DNA Plastids: Chloroplast: Green, photosynthesis, has DNA Endoplasmic Reticulum (ER): Rough ER: Protein synthesis Smooth ER: Lipid synthesis Golgi Apparatus: Modifies & packages proteins Lysosome...
Read more